If you’re talking about the 2021 Blizzconline, then no they never said no to Inarius being in Diablo 4.
The question was:
“Were we ever close to Inarius’ prison during our Diablo Adventures?”
That question had to do with Where inarius was imprisoned as well as whether we were ever close to it in Diablo 1, 2, and 3. Which is understandably no, as Inarius’s prison would be located in Mephisto’s domain, the realm of Hate, somewhere we’ve never been to in the previous games.
The Hellforge where we destroyed Mephisto’s and Diablo’s soulstone in Diablo 2, is located in Baal’s Domain.
Taken from the Book of Cain:
“He spoke of the Hellforge, located in the deepist pit of the Realm of Destruction. It was here that the demnoic smiths forged Hell’s most powerful weapons. Thus, it was said that the dread Hellforge held many unholy anvils, and among them was the Anvil of Annihilation. It was upon this anvil that angelic weapons and artifacts were destroyed. Legends held that anything broken upon the Anvil of Annihilation, no matter how powerful, would be forever negated.”
Now I’m sure if we ever saw the hellforge again in a future Diablo game, it’d be far more glorified than how we saw it in Diablo 2, similar to how different the Pandemonium fortress looks in Diablo 3 compared to how it looked in Diablo 2.
That specific question was pertaining to the previous games. As I said, the question itself had nothing to do with whether or not we’ll see Inarius in Diablo 4, but rather if we’ve ever been close to Inarius’s prison.
On the other hand, if the question was instead:
“Will we get close to Inarius’s prison during our Diablo Adventures.”
Then I’d be inclined to agree, as that would pertain to Diablo 4 as well.